The present invention relates to an automatic securement device for a cycle pedal, particularly but not exclusively, for an all terrain cycle pedal. It also relates to a pedal provided with such a device.
Automatic cycle pedals of this type are known, comprising a front securement member constituted by a claw forming an abutment to engage the front male end of a hooking member in the form of a plate forming a chock generally disposed in a hollow of the sole of a cyclist""s shoe, and a rear male engagement member constituted by a movable claw to engage a rear female end of the securement member.
On known pedals of this type, a male configuration at the front end of the chock is thus received in a female configuration of the front engagement member of the pedal.
The rear claw is mounted pivotably about an axle and is prestressed by resilient means toward an engagement position whilst being displaceable under the pressure of the shoe of the cyclist, between an open spaced position permitting the insertion of the chock between the two claws and a closed engagement position ensuring the securement of the chock with the automatic pedal.
The resilient means is generally constituted by a helical spring and the rear claw can be moved forcibly against the action of the spring, toward its open position to disengage the chock from its engagement between the claws. This movement of the rear claw is effected with the rear end of the chock whose female configuration has oblique side walls forming cams which, during rotation of the shoe outwardly, presses back the claw rearwardly. This movement of the rear claw toward the open position can moreover be obtained in the same manner during rotation of the shoe inwardly, for example if the cyclist falls. The tension of the spring can generally be adjusted with the help of an adjustment screw to modify the force necessary to disengage the shoe.
There is also known from French patent application 5 99.0914 in the name of the applicant, an automatic cyclist pedal, in particular for an all terrain cycle. This automatic pedal is a double surface retention pedal.
In this pedal, the rear movable member for engagement of the hooking element constitutes a resilient member fixed flush on the body of the pedal and working by bending between a bent release position for the hooking element and a retaining position of the latter against a retaining surface on the body of the pedal. The tension of this resilient element can be adjusted by movement of a plate whose upper edge defines the bend line of the resilient element.
On the chock that is used, the front and rear ends of said element are ends with a female configuration adapted to be by tongs between the front and rear male engagement members of the automatic pedal.
In this type of pedal, in which the chock is located in a recess or hollow of the sole, there are however sometimes problems for the disengagement of the shoe, whether such disengagement is triggered by the cyclist who rotates his foot outwardly, or whether it is triggered by the fall of the cyclist during which one of his feet can be caused to pivot inwardly or toward the inside. This is all the more critical for pedals in practice on all terrain cycles where falls are more frequent.
In existing pedal, there is also the need to facilitate the engagement of the chock between the claws during engaging the shoe, by reducing the force required from the cyclist.
The object of the invention is to provide a pedal adapted to overcome the drawbacks of pedals that are already known, by providing a securement device permitting easy engagement of the chock on the pedal and which at the same time reduces the forces necessary for engaging and disengaging the shoe, whilst ensuring the holding of the chock in an effective manner between the engagement elements.
The invention has for its object a device for the automatic securement of a cyclist""s shoe on a bicycle pedal, particularly for an all terrain bicycle, comprising in combination:
on the one hand a plate forming a chock secured to a shoe sole and disposed in a hollow of the latter, comprising side edges extending on opposite sides of the chock,
on the other hand securement means disposed on the pedal and adapted to secure said chock to the pedal, said securement means on the pedal comprising a fixed front engagement member and a rear movable engagement member each having a male configuration adapted to coact with a female configuration disposed at the front respectively the rear of the chock, characterized in that the rear movable engagement member is disposed between two fixed projecting members forming simultaneously a non-return abutment toward the rear and lateral slope adapted to coact with a side edge of said hollow of the shoe for the lateral engagement of the shoe by lateral pivoting of the shoe.
According to other characteristics of the invention:
said projecting members on the pedal body have a height such that the rear movable engagement member will be substantially level with the projecting members;
the rear movable engagement member has an opposite sides of its body a slight play relative to the two projecting members;
the angle of inclination of the slope is of the order of 45xc2x0;
each of said projecting members has a rearwardly inclined abutment surface;
the angle of inclination to the vertical is about 3xc2x0;
the chock is held between the front and rear engagement members with play, permitting a certain freedom of movement of the chock in translation in the longitudinal direction of the pedal body against the action of a resilient means (12), and this freedom of longitudinal movement has a value less than the engagement of the portion of the chock below the front engagement means so as to prevent the untimely disengagement of the shoe rearwardly during upward swinging of the latter.
Another object of the invention is a pedal provided with a securement device according to the invention.